ESTABLISHMENT AND USE OF ALTERNATIVE DEFINITIVE HOSTS FOR ECHINOCOCCUS

在口服原头节接种强的松龙治疗的蒙古沙鼠和金仓鼠的小肠中成功地恢复了妊娠的成年囊虫，建立了多房棘球蚴的替代最终宿主模型。这为在实验室中单独使用啮齿动物维持小鼠的完整生命周期铺平了道路。利用来自北美大陆的10种异齿科和大齿亚科野生啮齿动物，研究了这种“寄主容忍度”（即作为替代最终寄主的能力）的种间范围。从袋鼠大鼠和口袋鼠身上回收了未成熟的胚胎。在5个自交系中，AN系最敏感。肠道上皮黏液被认为可以阻止小鼠、仓鼠和蒙古沙鼠的初始建立。在泼尼松龙治疗和未治疗的动物之间粘膜肥大细胞数量的差异表明细胞对寄生虫的防御作用。在仓鼠中也观察到对寄生虫再感染的获得性免疫。泼尼松龙治疗的仓鼠胆道胆固醇浓度可能是对该类药物易感性的一个指标。在用可的松处理过的仓鼠、蒙古沙鼠、沙鼠和土鼠等宿主感染颗粒绦虫的实验中，未成熟的绦虫只能在感染后10天内恢复。通过使用替代最终宿主模型系统和实验感染犬，我们开发了一种可靠的犬棘球蚴感染免疫诊断方法。该试验采用夹心酶联免疫吸附试验（ELISA），利用单克隆抗体检测热稳定的粪原抗原。

An alternative definitive host model for echinococcus multilocularis was established following the successful recovery of gravid adult cestode from the small intesine of prednisolone-treated Mongolian gerbil and golden hamster after oral inoculation of protoscoleces. This paves the way for maintaining the complete life-cycle of the cestode in laboratory using rodents alone. The interspecies range of such "host permissiveness", that is, the ability to serve as alternative definitive host, for the cestode was examined using 10 species of wild rodents belonging to the family Heteromydae and sub-family Hesperomynae from the north American continent. Immature cestode were recovered from the Kangaroo rat and also from the pocket mouse. Of the 5 inbred strains of hamster evaluated, the AN strain was the most susceptible. Intestinal epithelial mucus was thought to prevent the initial establishment of the cestode in the mice, hamster and Mongilian gerbil. Differences in the number of mucosal mast cells between prednisolone-treated and non-treated animals suggest the defensive role of the cell against the parasite. Acquired immunity to reinfection of the cestode was also observed in hamster. Biliary cholesterol concentration of prednisolone-treated hamster might be an indicator for susceptibility to the cestode. In experiments involving E. granulosus infection in cortisone- treated hosts such as hamster, Mongolian gerbil, Akodon and Oryzomys, immature cestodes could be recovered only up to day 10 postinfection. By using the alternative definitive host model system and experimentally infected dogs, we have developed a reliable immunodiagnositic test for Echinococcus infection in dogs. The test involves the detection of heat- stable coproantigen by sandwich ELISA using a monoclonal antibody.